1. Field of the Invention
The present invention relates to a printing apparatus and method, and more particularly, to a printing apparatus and method having a security function involving user authorization by means of a password or the like.
2. Background of the Invention
Along with the advance of networking technology over the recent years, network-compatible printing apparatuses including printers, facsimiles and copying machines have come into practical use, and printing systems in which these printing apparatuses are connected to a network to enable many users to share a small number of printing apparatuses for printing purposes are coming into extensive use.
On the other hand, as the documents to be printed may contain such items of confidential information as information on personnel administration and personal information, the following two techniques, for example, are proposed to make possible secured print, which would prevent other parties from seeing the contents of printed matters in an environment of sharing printing apparatuses.
As one of these examples, Japanese Patent Application Laid-Open No. 2000-222150 proposes a printing system consisting of a host computer and printing apparatuses both connected to a network, wherein, when secured print is to be done, a printing job to which a password is added is transmitted to a printing apparatus, the password is also recorded on a floppy disk, and password collation is done via the floppy disk inserted into the printing apparatus to realize secured print. As another example, Japanese Patent Application Laid-Open No. 2001-039608 proposes a printing apparatus having an intermediate tray for stapling use, which realizes secured print in a simple way by temporarily storing printed sheets in the intermediate tray even if no stapling instruction is given, and ejecting the bundles of printing jobs to a paper discharging tray at once when all the jobs have been completed, thereby making it possible to keep the contents of the printed matters invisible until the printing is wholly completed.
However, both examples of the related art described above concern the mechanism of secured print itself, but neither makes any reference to the handling of a plurality of jobs. In the operation of secured print in a real office environment, since a plurality of users share the same printing apparatus for their common use, even if one of them tries to operate secured print for a confidential document, the printing apparatus may often be used for printing another document, and in such a case this user would have to wait in front of the printing apparatus until that printing job of somebody else is finished. Furthermore, during an operation to execute secured print such as undoing the restriction by the password, the job of someone else may be received.
Since secured print, very because of its nature, is an act that is done when the product of printing should not be seen by any unauthorized person, the user intending to do it has to wait in front of the printing apparatus, and in some cases he may have to wait in front of the printing apparatus until both the other person's printing job and his own secured print job end.
Further, the greater the number of persons sharing a printing apparatus, the more probable the printing apparatus is in operation, and to avoid this situation, the user has to execute secured print after confirming that the printing apparatus is not in printing operation; this circumstance makes secured print practically inconvenient in a usual office environment in which each printing apparatus is shared by a plurality of users.
In order to fundamentally solve these problems, the only available solution is to install an additional printing apparatus or apparatuses and reduce the utilization rate of each printing apparatus, but this is too costly a proposition to be realistic.
Thus, Japanese Patent Application Laid-Open No. 2000-222150 and Japanese Patent Application Laid-Open No. 2001-039608 cited above take no heed of the mutual problems which are likely to occur among a plurality of users sharing one printing apparatus, and cannot contribute to increasing the convenience of secured print in an existing printing system built up in a usual office environment.